despair vs pessimism

despair

noun
  • That which is despaired of. 

  • That which causes despair. 

  • Loss of hope; utter hopelessness; complete despondency. 

verb
  • To be hopeless; to have no hope; to give up all hope or expectation. 

  • To cause to despair. 

pessimism

noun
  • The condition of being pessimal. 

  • A general belief that bad things will happen. 

  • The doctrine that this world is the worst of all possible worlds. 

How often have the words despair and pessimism occurred in a corpus of books? (source: Google Ngram Viewer )